Identification of character-impact odorants in coriander and wild coriander leaves using gas chromatography-olfactometry (GCO) and comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–TOFMS)

Characterization of volatile profile from different coriander (Coriandrum sativum L.) varieties via HS-SPME/GC-MS combined with E-nose analyzed by chemometrics

Headspace-solid phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) and electronic nose (E-nose) technologies were implemented to characterize the volatile profile of aerial part from 40 coriander varieties. A total of 207 volatile compounds were identified and quantified, including aldehydes, alcohols, terpenes, hydrocarbons, esters, ketones, acids, furans, phenols and others. E-nose results showed that W5S and W2W were representative sensors responding to coriander odor. Among all varieties, the number (21-30 species) and content (449.94-1050.55 μg/g) of aldehydes were the highest, and the most abundant analytes were (Z)-9-hexadecenal or (E)-2-tetratecenal, which accounted for approximately one-third of the total content. In addition, 37 components were determined the characteristic constituents with odor activity values (OAVs) ≥ 1, mainly presenting citrusy, fatty, soapy and floral smells. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) could effectively distinguish different varieties. This study provided a crucial theoretical basis for flavor evaluation and quality improvement of coriander germplasm resources.

Eryngial: An α,β-Unsaturated Fatty Aldehyde as the Major Phytotoxin in Spiny Coriander (Eryngium foetidum L.) Essential Oil

Weed species many times possess allelochemicals as a part of their survival strategy. These metabolites can be potential targets in search of natural phytotoxins. This study aims to evaluate the phytotoxic ability of fatty aldehyde-rich essential oil from spiny coriander (Eryngium foetidum) leaves, also known as fitweed or spiritweed and to further identify the active phytotoxins. This oil dose-dependently inhibited the wheatgrass coleoptile and radicle growth in multiple bioassays with half maximal inhibitory concentration (IC50) 30.6-56.7 μg/mL, while exhibiting a less pronounced effect on the germination (IC50 181.8 μg/mL). The phytotoxicity assessment of two oil constituents identified eryngial (trans-2-dodecenal), exclusively major fatty aldehydic constituent as the potent growth inhibitor with IC50 in the range 20.8-36.2 μg/mL during an early phase of wheatgrass emergence. Eryngial-inspired screening of eleven saturated fatty aldehydes and alcohols did not find a significantly higher phytotoxic potency. In an open vessel, eryngial as the supplementation in agar medium, dose-dependently inhibited the growth of pre-germinated seeds of one monocot (bermudagrass) and one dicot (green amaranth) weed species with IC50 in the range 23.8-65.4 μg/mL. The current study identified eryngial, an α,β-unsaturated fatty aldehyde of coriander origin to be a promising phytotoxic candidate for weed control.

The use of gas chromatography combined with chemical and sensory analysis to evaluate nuisance odours in the air and water environment

Varieties of gas chromatography (GC) combined with chemical detection (CD) and sensory analysis at the odour detection port (ODP) for the evaluation of environmental odorants has steadily increased in application and sophistication; this has given rise to a plethora of techniques that cater to specific tasks. With this diversity of approaches in mind, there is a need to assess the critical points at which these approaches differ, as well as likely risks and factors that may affect them. These critical points explained within this review include sample preparation, GC separation techniques (with associated co-elution risks), how the elute is separated between CD and sensory analysis, the type of CD, the type of sensory analysis (with particular attention paid to its factors and guidelines), integrative data techniques, as well as how that data may be used. Additionally, this review provides commentary on the current state of the research space and makes recommendations based on how these analyses should be reported, the standardisation of nomenclature, as well as the impediments to the future goals of this research area. By careful consideration of the critical points of varying analytical processes and how best to communicate these findings, the quality of output within this area will improve. This review provides a benchmark for how GC-CD/sensory analysis should be undertaken and reported.

Biocatalytic Production of Odor-Active Fatty Aldehydes from Fungal Lipids

Odor-active fatty aldehydes are important compounds for the flavor and fragrance industry. By a coupled enzymatic reaction using an α-dioxygenase (α-DOX) and an aldehyde dehydrogenase (FALDH), scarcely available aldehydes from the biotransformation of margaroleic acid [17:1(9Z)] were characterized and have shown highly interesting odor profiles, including citrus-like, soapy, herbaceous, and savory notes. In particular, (Z)-8-hexadecenal and (Z)-7-pentadecenal exhibited notable meaty odor characteristics. Submerged cultivation of Mortierella hyalina revealed the accumulation of the above-mentioned, naturally uncommon fatty acid 17:1(9Z). Its production was significantly increased by the modulation of culture conditions, whereas the highest accumulation was observed after 4 days at 24 °C and l-isoleucine supplementation. The lipase-, α-DOX-, and FALDH-mediated biotransformation of M. hyalina lipid extract resulted in a complex aldehyde mixture with a high aldehyde yield of ∼50%. The odor qualities of the formed aldehydes were assessed by means of gas chromatography-olfactometry, and several of the obtained fatty aldehydes have been sensorially described for the first time. To assess the aldehyde mixture's potential as a flavor ingredient, a sensory evaluation was conducted. The obtained product exhibited intense citrus-like, green, and soapy odor impressions.

The human odorant receptor OR10A6 is tuned to the pheromone of the commensal fruit fly Drosophila melanogaster

All living things speak chemistry. The challenge is to reveal the vocabulary, the odorants that enable communication across phylogenies and to translate them to physiological, behavioral, and ecological function. Olfactory receptors (ORs) interface animals with airborne odorants. Expression in heterologous cells makes it possible to interrogate single ORs and to identify cognate ligands. The cosmopolitan, anthropophilic strain of the vinegar fly Drosophila melanogaster depends on human resources and housing for survival. Curiously, humans sense the pheromone (Z)-4-undecenal (Z4-11Al) released by single fly females. A screening of all human ORs shows that the most highly expressed OR10A6 is tuned to Z4-11Al. Females of an ancestral African fly strain release a blend of Z4-11Al and Z4-9Al that produces a different aroma, which is how we distinguish these fly strains by nose. That flies and humans sense Z4-11Al via dedicated ORs shows how convergent evolution shapes communication channels between vertebrate and invertebrate animals.

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Humans sense the sex pheromone Z411-Al released by single Drosophila melanogaster females

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The most highly expressed human olfactory receptor OR10A6 is tuned to Z411-Al

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An African fly strain emits two aldehydes, which we distinguish from Z411-Al by nose

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Convergent evolution shapes chemical communication between phylogenies

An enzymatic tandem reaction to produce odor-active fatty aldehydes

Abstract

Aldehydes represent a versatile and favored class of flavoring substances. A biocatalytic access to odor-active aldehydes was developed by conversion of fatty acids with two enzymes of the α-dioxygenase pathway. The recombinant enzymes α-dioxygenase (α-DOX) originating from Crocosphaera subtropica and fatty aldehyde dehydrogenase (FALDH) from Vibrio harveyi were heterologously expressed in E. coli, purified, and applied in a coupled (tandem) repetitive reaction. The concept was optimized in terms of number of reaction cycles and production yields. Up to five cycles and aldehyde yields of up to 26% were achieved. Afterward, the approach was applied to sea buckthorn pulp oil as raw material for the enzyme catalyzed production of flavoring/fragrance ingredients based on complex aldehyde mixtures. The most abundant fatty acids in sea buckthorn pulp oil, namely palmitic, palmitoleic, oleic, and linoleic acid, were used as substrates for further biotransformation experiments. Various aldehydes were identified, semi-quantified, and sensorially characterized by means of headspace–solid phase microextraction–gas chromatography–mass spectrometry–olfactometry (HS–SPME–GC–MS–O). Structural validation of unsaturated aldehydes in terms of double-bond positions was performed by multidimensional high-resolution mass spectrometry experiments of their Paternò–Büchi (PB) photoproducts. Retention indices and odor impressions of inter alia (Z,Z)-5,8-tetradecadienal (Z,Z)-6,9-pentadecadienal, (Z)-8-pentadecenal, (Z)-4-tridecenal, (Z)-6-pentadecenal, and (Z)-8-heptadecenal were determined for the first time.

Key points

• Coupled reaction of Csα-DOX and VhFALDH yields chain-shortened fatty aldehydes.

• Odors of several Z-unsaturated fatty aldehydes are described for the first time.

• Potential for industrial production of aldehyde-based odorants from natural sources.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00253-022-12134-3.

Evaluation of the composition and in vitro antimicrobial, antioxidant, and anti-inflammatory activities of Cilantro (Coriandrum sativum L. leaves) cultivated in Saudi Arabia (Al-Kharj)

Background

In the present study, we explored the composition of Cilantro (Coriandrum sativum L. leaves) essential oil (CEO) cultivated in Saudi Arabia (Al-Kharj) and explored its antioxidant, antimicrobial, and anti-inflammatory effects in vitro.

Methods

Gas chromatography-mass spectroscopy was used to detect the CEO composition. The 2, 2-diphenyl-1-picrylhydrazyl (DPPH)-induced free radical and ferric chloride scavenging methods were used to determine the antioxidant activity. Antimicrobial activity was investigated using the well diffusion method. Anti-inflammatory activity was evaluated using egg albumin and trypsin-induced inflammation methods.

Results

Forty-six compounds representing 90.17% of the total aroma were identified in the CEO; the major constituents were found to be 1-decanol (17.85%), decanal (11.04%), trans-2-dodecen-1-ol (7.87%), menthone (6.71%), 2-decen-1-ol, trans- (5.44%), dodecanal (4.76%), trans-tetradec-2-enal (3.14%), sedanolide (3.02), and thymol (3.01%). DPPH-induced free radical and ferric chloride scavenging assays demonstrated low antioxidant effects of CEO, and the antioxidant activity was observed at a high CEO concentration. The antimicrobial activity of CEO was assessed against 5 microorganisms (bacteria and fungi) by using well diffusion methods; CEO was found to possess excellent antimicrobial activity against all microorganisms, except Escherichia coli. Moreover, CEO demonstrated strong anti-inflammatory activity against egg albumin- and trypsin-induced inflammation.

Conclusion

The essential oil extracted from C. sativum chemotype grown in Al-Kharj region of Saudi Arabia possesses low antioxidant potential, superior antimicrobial activity, and outstanding anti-inflammatory effects.

Concentrations-dependent effect of exogenous abscisic acid on photosynthesis, growth and phenolic content of Dracocephalum moldavica L. under drought stress

The drought conditions and the application of ABA reduce the photosynthetic activity, and the processes related to the transpiration of Dracocephalum moldavica L. At the same time, the plant increases the production of phenolic compounds and essential oil as a response to stress conditions. In the semi-arid regions, drought stress is the most important environmental limitations for crop production. Abscisic acid (ABA) plays a crucial role in the reactions of plants towards environmental stress such as drought. Field experiments for two consecutive years in 2016 and 2017 were conducted to evaluate the effect of three watering regimes (well-watered, moderate and severe drought) and five exogenous ABA concentrations (0, 5, 10, 20 and 40 μM) on growth, photosynthesis, total phenolic and essential oil content of Dracocephalum moldavica L. Without ABA application, the highest photosynthetic rate (6.1 μmol CO₂ m^-2 s^-1) was obtained under well-watered condition and, moderate and severe drought stress decreased photosynthesis rate by 26.39% and 34.43%, respectively. Some growth parameters such as stem height, leaf area, leaf dry weight and biological yield were also reduced by drought stress. ABA application showed a decreasing trend in photosynthesis rate and mentioned plant growth parameters under all moisture regimes. The highest seed yield (1243.56 kg ha^-1) was obtained under well-watered condition without ABA application. Increasing ABA concentration decreased seed yield in all moisture regimes. The highest total phenolic content (8.9 mg g^-1 FW) and essential oil yield (20.58 kg ha^-1) were obtained from 20 and 5 μM ABA concentration, respectively, under moderate drought stress.

Coriandrum sativum L.-Effect of Multiple Drying Techniques on Volatile and Sensory Profile

Coriandrum sativum L. is a medicinal and aromatic plant spread around the world, with beneficial properties that are well recognized. Both coriander seeds and leaves are used for pharmaceutical and flavoring purposes. Even though coriander seeds tend to be more popular, the leaves are receiving a consistently growing interest, especially because of popularization of Mexican, Northern African, and Indian cuisines. This increased attention brings about the necessity for providing the product with guaranteed quality, which will retain its valuable characteristics, even after post-harvest treatment. For this reason, it is highly necessary to determine reliable protocols for cilantro preservation, which usually include drying procedures; in order to identify the optimal drying treatments, a spectrum of drying techniques-convective, vacuum-microwave, and a combination of convective and vacuum-microwave-were evaluated. Cilantro-based dried products were examined from the perspectives of volatile organic constituent composition and sensory quality. After headspace solid-phase microextraction-GC/MS analysis and sensory tests, the results demonstrate that convective drying at 70 °C for 120 min followed by vacuum-microwave drying at 360 W and convective drying at 70 °C were the optimal drying methods for preserving cilantro aroma quality, while convective drying at 70 °C for 120 min followed by convective finishing drying at 50 °C decreased cilantro aroma quality.

The Variability of Thymol and Carvacrol Contents Reveals the Level of Antibacterial Activity of the Essential Oils from Different Accessions of Oliveria decumbens

Oliveria decumbens (Apiaceae) is an aromatic herb traditionally employed in the Persian medicine for the treatment of infectious and gastrointestinal disorders. In the present study, we analyzed the chemical composition of essential oils obtained from different Iranian populations and evaluated their efficacy on a panel of human pathogens (Staphylococcus aureus and Escherichia coli), probiotic (Bacillus subtilis), and phytopathogens (Clavibacter michiganensis, Curtobacterium flaccumfaciens, Xanthomonas citri, and Agrobacterium tumefaciens). The gas chromatographic-mass spectrometry analysis put in evidence four main volatile constituents such as thymol (20.3–36.4%), carvacrol (18.8–33.1%), γ-terpinene (10.6–25.9%), and p-cymene (9.5–17.3%), though with significant variability from an essential oil to another. Notably, the oils from the populations sited in Nourabad Mamasani and Dehdasht showed the highest amount of the phenolic monoterpenes thymol (36.4 and 35.2%, respectively) and carvacrol (33.1 and 30.6%, respectively). The antibacterial activity of O. decumbens essential oils was assessed by the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) methods, showing high activity for the samples from Nourabad Mamasani and Dehdasht populations exhibiting high level of the above phenolics. The obtained MIC and MBC values (mg/ml) were in the ranges 0.0625–2 mg/ml and 1–16 mg/ml, respectively. Noteworthy, in some cases, the antibacterial activity of O. decumbens essential oils was higher than that of chloramphenicol used as positive control. The average MBCs displayed by the O. decumbens samples showed that C. flaccumfaciens had the highest sensitivity to the essential oils. Based on these results, our work shed light on selected O. decumbens populations deserving proper breeding and cultivation strategies in order to warrantee production of bioactive essential oils to be used at pharmaceutical and agricultural level to combat several pathogens.

Chemical Compositions of Commercial Essential Oils From Coriandrum sativum Fruits and Aerial Parts

Coriander and cilantro, the fruit and herb of Coriandrum sativum, are popular additives in various cuisines worldwide. The essential oils derived from coriander and cilantro are also popular and have shown some remarkable biological properties and health benefits. In this report, we have analyzed the essential oil compositions of 19 commercial coriander and 28 commercial cilantro essential oil samples by gas chromatography–mass spectrometry (GC–MS) techniques. In addition, 5 coriander and 4 cilantro commercial essential oil samples were analyzed by chiral GC–MS. Commercial coriander essential oil is dominated by linalool (62.2%-76.7%) with lesser quantities of α-pinene (0.3%-11.4%), γ-terpinene (0.6%-11.6%), and camphor (0.0%-5.5%). Commercial cilantro essential oil is composed largely of (2 E)-decenal (16.0%-46.6%), linalool (11.8%-29.8%), (2 E)-decen-1-ol (0.0%-24.7%), decanal (5.2%-18.7%), (2 E)-dodecenal (4.1%-8.7%), and 1-decanol (0.0%-9.5%). The enantiomeric distribution of linalool was 87% (+)-linalool:13% (−)-linalool in both coriander and cilantro essential oils, while α-pinene was 93% (+):7% (−) in coriander, 90% (+):10% (−) in cilantro; and (+)-camphor:(−)-camphor was 13%:87% in both essential oils. Chiral GC–MS analysis was able to detect an adulterated coriander essential oil sample. The data provided in this study serves to establish a baseline for future evaluations of these essential oils as well as a screen for authenticity or adulteration.

Growth Spectrum Complexity Dictates Aromatic Intensity in Coriander (Coriandrum sativum L.)

Advancements in availability and specificity of light-emitting diodes (LEDs) have facilitated trait modification of high-value edible herbs and vegetables through the fine manipulation of spectra. Coriander (Coriandrum sativum L.) is a culinary herb, known for its fresh, citrusy aroma, and high economic value. Studies into the impact of light intensity and spectrum on C. sativum physiology, morphology, and aroma are limited. Using a nasal impact frequency panel, a selection of key compounds associated with the characteristic aroma of coriander was identified. Significant differences (P < 0.05) were observed in the concentration of these aromatics between plants grown in a controlled environment chamber under the same photosynthetic photon flux density (PPFD) but custom spectra: red (100%), blue (100%), red + blue (RB, 50% equal contribution), or red + green + blue (RGB, 35.8% red: 26.4% green: 37.8% blue) wavelengths. In general, the concentration of aromatics increased with increasing numbers of wavelengths emitted alongside selective changes, e.g., the greatest increase in coriander-defining E-(2)-decenal occurred under the RGB spectrum. This change in aroma profile was accompanied by significant differences (P < 0.05) in light saturated photosynthetic CO2 assimilation, water-use efficiency (Wi), and morphology. While plants grown under red wavelengths achieved the greatest leaf area, RB spectrum plants were shortest and had the highest leaf:shoot ratio. Therefore, this work evidences a trade-off between sellable commercial morphologies with a weaker, less desirable aroma or a less desirable morphology with more intense coriander-like aromas. When supplemental trichromatic LEDs were used in a commercial glasshouse, the majority of compounds, with the exception of linalool, also increased showing that even as a supplement additional wavelength can modify the aromatic profile increasing its complexity. Lower levels of linalool suggest these plants may be more susceptible to biotic stress such as herbivory. Finally, the concentration of coriander-defining aromatics E-(2)-decenal and E-(2)-hexenal was significantly higher in supermarket pre-packaged coriander leaves implying that concentrations of aromatics increase after excision. In summary, spectra can be used to co-manipulate aroma profile and plant form with increasing spectral complexity leading to greater aromatic complexity and intensity. We suggest that increasing spectral complexity progressively stimulates signaling pathways giving rise to valuable economic traits.

The Blossoming of Technology for the Analysis of Complex Aroma Bouquets-A Review on Flavour and Odorant Multidimensional and Comprehensive Gas Chromatography Applications

Multidimensional approaches in gas chromatography have been established as potent tools to (almost) attain fully resolved analyses. Flavours and odours are important application fields for these techniques since they include complex matrices, and are of interest for both scientific study and to consumers. This article is a review of the main research studies in the above theme, discussing the achievements and challenges that demonstrate a maturing of analytical separation technology.

Assessment of main factor causing sensory quality defects in chicken seasoning during storage

BACKGROUND

Chicken seasoning is a widely consumed palatable seasoning made with chicken meat. Quality, and especially sensory quality, may determine the consumer choice of food. The same bag of chicken seasoning will be stored by the consumers over a long period of time when it is in use, so it is particularly important to be able to assess its sensory quality. However, the sensory quality defects of chicken seasoning during storage remain unknown. This study evaluated flavor changes in chicken seasoning during storage using sensory evaluation and gas chromatography-mass spectrometry (GC-MS).

RESULTS

The sensory evaluation indicated a perceptible change in rancidity during storage. The GC-MS results showed increases in the content of aldehydes, heterocyclic compounds, ketones, and sulfur compounds associated with lipid oxidation. A random forest model was constructed to predict the storage time based on the data for volatile compounds related to lipid oxidation. The low average predicted error indicated a good correlation between lipid oxidation and storage time.

CONCLUSION

These results suggest that lipid oxidation is the main factor behind sensory quality defects in chicken seasoning during storage. This can be used as the basis for further evaluation of sensory quality and the shelf life of chicken seasoning. © 2018 Society of Chemical Industry.

Addressing the Challenges to Identification in Gas Chromatography by Increased Resolution and Enhanced Detection Modalities

In the past 15+ years, gas chromatography (GC) has undergone a renaissance in its implementation on the basis of the "disruptive" technology of comprehensive two-dimensional gas chromatography (GC×GC). With a foundation based upon a two-column GC separation approach, GC×GC significantly alters the classical multidimensional gas chromatography (MDGC) method by employing very fast separation on a second dimension (2 D) after a conventional one-dimensional (i.e., single column; 1D) column separation. This allows the experimentalist to apply the advantages of multidimensionality to the total sample rather than to just discrete zones of the 1D separation that characterizes MDGC. This requires a new "language" to describe GC×GC separations, applied to the first dimension (1 D) and 2 D, and consideration of the modulation processes that define the transfer of analyte from the 1 D to the 2 D. The present review is based on the FACS Foundation lectureship of the author given at the 17th Asian Chemical Congress of the Federation of Asian Chemical Societies (FACS). The award lecture and this manuscript is based on material deriving largely from research in the area of MDGC and GC×GC separations of the author.

Investigation on the antimicrobial activities of gingers (Etlingera coccinea (Blume) S.Sakai & Nagam and Etlingera sessilanthera R.M.Sm.) endemic to Borneo

AIMS

To investigate the antimicrobial properties of Etlingera coccinea and Etlingera sessilanthera and to isolate and identify the antimicrobial compounds.

METHODS AND RESULTS

Extracts were obtained via sequential solvent extraction method using hexane, dichloromethane, ethyl acetate, methanol and water. Antimicrobial activity testing was done using broth microdilution assay against 17 strains of bacteria. The leaf hexane extract of E. coccinea and rhizome hexane extract of E. sessilanthera showed best antimicrobial activities, with minimum inhibitory concentration (MIC) values ranging from 0·016 to 1 mg ml-1 against Gram-positive bacteria. From these active extracts, two antimicrobials were isolated and identified as trans-2-dodecenal and 8(17),12-labdadiene-15,16-dial with MIC values ranging from 4 to 8 μg ml-1 against Bacillus cereus, Bacillus subtilis and Staphylococcus aureus.

CONCLUSION

Etlingera coccinea and E. sessilanthera demonstrated good antimicrobial activities against clinically relevant bacteria strains. The antimicrobial compounds isolated showed low MIC values, hence suggesting their potential use as antimicrobial agents.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study is the first to identify the potent antimicrobials from these gingers. The antimicrobials isolated could potentially be developed further for use in treatment of bacterial infections. Also, this study warrants further research into other Etlingera species in search for more antimicrobial compounds.

Eryngium foetidum L. Essential Oils: Chemical Composition and Antioxidant Capacity

Background:Eryngium foetidum essential oils from Nigeria were investigated for the first time in order to ascertain their potency as natural antioxidants. E. foetidum is an aromatic and medicinal herb used in ethno-medicine and as a traditional spice for foods. Methods: The hydro-distilled oils of E. foetidum were subjected to gas chromatography-mass spectrometry (GC-MS) analysis. Free radical scavenging capacity of the volatile oils was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Results: Leaf volatile oil contained a high proportion of (E)-2-Dodecenal (28.43%), 13-tetradecenal (27.45%), dodecanal (14.59%) and 2,4,5-trimethylbenzaldehyde (10.77%); the stem oil comprised of dodecanal (20.21%), 2,4,5-trimethylbenzaldehyde (18.43%) and (E)-2-dodecenal (8.27%), while 2,4,5-trimethylbenzaldehyde (56.08%), 13-tetradecenal (9.26%) and (E)-2-dodecenal (7.65%) were the most dominant in the root oil. The IC₅₀ values for the leaf, stem and root oils were 56 µg/mL, 46µg/mL and 54.5 µg/mL respectively in the DPPH assay while the leaf oil exhibited the highest reducing potential among the test oils in the FRAP assay. Conclusions: The Nigerian E. foetidum volatile oils contain high amount of acyclic aldehydes and aromatic compounds. The oils are a potential source of natural antioxidant as demonstrated by their strong antioxidant activity.

Identification of aroma volatiles and understanding 2-acetyl-1-pyrroline biosynthetic mechanism in aromatic mung bean (Vigna radiata (L.) Wilczek)

Mung bean having high food value and easily digestible proteins, is one of the socioeconomically important crop of India. Among the varied cultivars, Sona mung is having aroma and hence popularly cultivated in the pockets of Ganga river basin at Bhutnir char village of Malda District in the West Bengal state. In the present study, aroma volatiles with special reference to 2-acetyl-1-pyrroline (2AP) were analyzed using HS-SPME-GCMS from Sona mung bean and compared with non-scented mung bean (PHULE M-9339). 26 volatiles in seeds of Sona mung and 20 in non-scented mung bean were identified, in which 3,7-dimethyl-6-octenal, (2E)-2-decen-1-ol, 2-ethyl-1-dodecanol and 3,5,5-trimethyl-2-cyclohexene-1-one are first time reported. 0.19 ± 0.001 ppm 2AP was recorded in Sona mung seeds whereas it was not detected in non-scented mung bean. PCA analysis indicated that 2AP, octanal, 1 pentanol, decanal, phenylmethanol and 2-nonen-1-ol were the major contributors in the aroma of Sona mung bean. The significantly higher level proline, methylglyoxal and lower level of BADH2 transcript were detected in Sona mung than non-scented mung, suggesting similar 2AP biosynthesis mechanism in Sona mung bean as reported in scented rice, sorghum and soybean.

Chemical Composition and Antimicrobial Activity of the Essential Oil from Flowers of Eryngium triquetrum (Apiaceae) Collected Wild in Sicily

The chemical composition of the essential oil from flowers of Eringium triquetrum Vahl. collected in Sicily was evaluated by GC and GC-MS. The main components were pulegone (50.6%), piperitenone (30.5%) and menthone (7.0%). Comparison of this oil with other studied oils of Eringium species is discussed. The oil showed good antibacterial and antifungal activities against some microorganisms that infest historical art works.

Identification of complex septic odorants in Huangpu River source water by combining the data from gas chromatography-olfactometry and comprehensive two-dimensional gas chromatography using retention indices

Identification of the trace odorants causing the septic odors in source waters with complex matrixes has long been a big challenge. The Huangpu (HP) River, an important source water for Shanghai, has long been suffering from septic and musty odors, although major odorants have not been identified. In this study, combining the data from gas chromatography-olfactometry with mass spectrometry (GC-O/MS) and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS) using retention indices (RIs) was used for the identification of odorants in HP source water. Olfactometry peaks detected in water extracts by GC-O/MS were combined with the chromatography peaks detected by GC×GC-TOFMS based on the RIs determined using the retention times (RTs) of alkanes C7-C30. A total of thirteen olfactometry peaks were obtained though GC-O/MS analysis, and potential odorants corresponding to each of the olfactometry peaks were screened based on the odor characteristics and match similarity using GC×GC-TOFMS. Finally, fourteen odorants (one odorant was detected in GC×GC-TOFMS without an olfactometry peak), including three septic odorants (bis(2-chloroisopropyl) ether, diethyl disulfide and dimethyl disulfide) and two musty ones (geosmin and 2-MIB), were confirmed by using authentic standards. The septic and musty odorants in six source water samples taken over a period of six months were quantified. Bis(2-chloroisopropyl) ether, with an odor activity value (OAV) of 1.84-3.2, was found to be a major septic odorant in HP source water, followed by diethyl disulfide (OAV 1.56-1.96) and dimethyl disulfide (OAV 0.37-2.42), while geosmin (OAV 4.37-11.44) was the major musty odorant, followed by 2-MIB (OAV 1.13-1.89). This is the first comprehensive study focusing on the identification of odorants in a complex source water. The integrated approach used in this study could be applied for the identification of odorants in other complex source waters suffering similar odor problems.

Enantioselective comprehensive two-dimensional gas chromatography. A route to elucidate the authenticity and origin of Rosa damascena Miller essential oils

The analysis of Bulgarian and Turkish Rosa damascena Miller essential oils was performed by flow-modulated comprehensive two-dimensional gas chromatography using simultaneous detection of the second column effluent by flame ionization and quadrupole mass spectrometric detection. Enantioselective separations were obtained by running the samples on 2,3-di-O-ethyl-6-O-tert-butyldimethylsilyl-β-cyclodextrin column as the first column and on polyethylene glycol as the second column. The determination of enantiomeric or diastereomeric excess of some terpenoic solutes is a possible route for quality or authenticity control as well as for the elucidation of the country of origin.

Coriander (Coriandrum sativum L.) and its bioactive constituents

Coriander (Coriandrum sativum L.), a member of the Apiaceae family, is among most widely used medicinal plant, possessing nutritional as well as medicinal properties. Thus, the aim of this updated review is to highlight the importance of coriander as a potential source of bioactive constituents and to summarize their biological activities as well as their different applications from data obtained in recent literature, with critical analysis on the gaps and potential for future investigations. A literature review was carried out by searching on the electronic databases including PubMed, Scopus, ScienceDirect, and Google Scholar for studies focusing on the biological and pharmacological activities of coriander seed and herb bioactive constituents. All recent English-language articles published between 2000 and 2014 were searched using the terms 'C. sativum', 'medicinal plant', 'bioactive constituents', and 'biological activities'. Subsequently, coriander seed and herb essential oils have been actively investigated for their chemical composition and biological activities including antimicrobial, antioxidant, hypoglycemic, hypolipidemic, anxiolytic, analgesic, anti-inflammatory, anti-convulsant and anti-cancer activities, among others. Although coriander has been reported to possess a wide range of traditional medicinal uses, no report is available in its effectiveness use in reactive airway diseases such as asthma and bronchiolitis. In brief, the information presented herein will be helpful to create more interest towards this medicinal species by defining novel pharmacological and clinical applications and hence, may be useful in developing new drug formulations in the future or by employing coriander bioactive constituents in combination with conventional drugs to enhance the treatment of diseases such as Alzheimer and cancer.

Activation of the Kelch-like ECH-associated protein 1 (Keap1)/NF-E2-related factor 2 (Nrf2) pathway through covalent modification of the 2-alkenal group of aliphatic electrophiles in Coriandrum sativum L

Phytochemicals able to activate the transcription factor NF-E2-related factor 2 (Nrf2) were isolated from an extract of Coriandrum sativum L. (C. sativum) leaves by preparative octadecyl silica column chromatography. Ultraperformance liquid chromatography and liquid chromatography-tandem mass spectrometry analysis of the isolated components after derivatization with 2-diphenylacetyl-1,3-inandione-1-hydrazone and experiments with HepG2 cells revealed that (E)-2-alkenals with different carbon numbers play a role in Nrf2 activation in these cells. Such Nrf2 activation appears to be attributable to S-alkylation of Kelch-like ECH-associated protein 1 (Keap1), the negative regulator for Nrf2, as determined by a biotin-PEAC5-maleimide assay. Interestingly, (E)-2-butenal caused Keap1 modification and Nrf2 activation, whereas butanal did not. These results suggest that (E)-2-alkenals with an α,β-unsaturated aldehyde moiety, which is a common substituent in phytochemicals isolated from C. sativum leaves, activate the Keap1/Nrf2 pathway associated with cellular protection.

Coriandrum sativum L. (Coriander) essential oil: antifungal activity and mode of action on Candida spp., and molecular targets affected in human whole-genome expression

Oral candidiasis is an opportunistic fungal infection of the oral cavity with increasingly worldwide prevalence and incidence rates. Novel specifically-targeted strategies to manage this ailment have been proposed using essential oils (EO) known to have antifungal properties. In this study, we aim to investigate the antifungal activity and mode of action of the EO from Coriandrum sativum L. (coriander) leaves on Candida spp. In addition, we detected the molecular targets affected in whole-genome expression in human cells. The EO phytochemical profile indicates monoterpenes and sesquiterpenes as major components, which are likely to negatively impact the viability of yeast cells. There seems to be a synergistic activity of the EO chemical compounds as their isolation into fractions led to a decreased antimicrobial effect. C. sativum EO may bind to membrane ergosterol, increasing ionic permeability and causing membrane damage leading to cell death, but it does not act on cell wall biosynthesis-related pathways. This mode of action is illustrated by photomicrographs showing disruption in biofilm integrity caused by the EO at varied concentrations. The EO also inhibited Candida biofilm adherence to a polystyrene substrate at low concentrations, and decreased the proteolytic activity of Candida albicans at minimum inhibitory concentration. Finally, the EO and its selected active fraction had low cytotoxicity on human cells, with putative mechanisms affecting gene expression in pathways involving chemokines and MAP-kinase (proliferation/apoptosis), as well as adhesion proteins. These findings highlight the potential antifungal activity of the EO from C. sativum leaves and suggest avenues for future translational toxicological research.

The Effects of Cooking Process and Meat Inclusion on Pet Food Flavor and Texture Characteristics

Simple Summary

The results of this research indicate that processing (baked vs. extruded) plays an important role in determining pet food product texture. In addition, raw ingredients (fresh meat vs. meal-based) did not consistently affect product sensory characteristics. These results may help pet food technologists better understand factors that affect palatability.

Abstract

The pet food industry is an important portion of the food and feed industries in the US. The objectives of this study were (1) to determine cooking method (baking or extrusion), meat inclusion (0 or 20%), and extrusion thermal to mechanical energy ratios (low, medium, and high) effects on sensory and volatile properties of pet foods, and (2) to determine associations among sensory and volatile characteristics of baked and extruded pet foods. Descriptive sensory analysis and gas chromatography-mass spectrometry were used to analyze the pet food samples. It was found that baked samples were lighter in color (2.0–2.6 baked vs. 3.5–4.3 extruded, color intensity scale 0–15), and had lower levels of attributes that indicated rancidity (i.e., fishy flavor; 0.3–0.6 baked, 0.6–1.5 extruded, scale 0–15), whereas extruded pet foods were more cohesive in mass, more friable, hard, and crisp, but less powdery than baked samples. Fresh meat inclusion tended to decrease bitterness and increase fishy flavor and cohesiveness of pet foods. High thermal to mechanical energy ratio during extrusion resulted in less musty and more porous kibbles. The main volatile compounds included aldehydes, such as hexanal and heptanal, ketones, and alcohols. Extruded samples did not contain methylpyrazine, while baked samples did not contain 2-butyl furan. Future studies should consider evaluating the relationship between sensory results and animal palatability for these types of foods.

Can volatile organic metabolites be used to simultaneously assess microbial and mite contamination level in cereal grains and coffee beans?

A novel approach based on headspace solid-phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–ToFMS) was developed for the simultaneous screening of microbial and mite contamination level in cereals and coffee beans. The proposed approach emerges as a powerful tool for the rapid assessment of the microbial contamination level (ca. 70 min versus ca. 72 to 120 h for bacteria and fungi, respectively, using conventional plate counts), and mite contamination (ca. 70 min versus ca. 24 h). A full-factorial design was performed for optimization of the SPME experimental parameters. The methodology was applied to three types of rice (rough, brown, and white rice), oat, wheat, and green and roasted coffee beans. Simultaneously, microbiological analysis of the samples (total aerobic microorganisms, moulds, and yeasts) was performed by conventional plate counts. A set of 54 volatile markers was selected among all the compounds detected by GC×GC–ToFMS. Principal Component Analysis (PCA) was applied in order to establish a relationship between potential volatile markers and the level of microbial contamination. Methylbenzene, 3-octanone, 2-nonanone, 2-methyl-3-pentanol, 1-octen-3-ol, and 2-hexanone were associated to samples with higher microbial contamination level, especially in rough rice. Moreover, oat exhibited a high GC peak area of 2-hydroxy-6-methylbenzaldehyde, a sexual and alarm pheromone for adult mites, which in the other matrices appeared as a trace component. The number of mites detected in oat grains was correlated to the GC peak area of the pheromone. The HS-SPME/GC×GC–ToFMS methodology can be regarded as the basis for the development of a rapid and versatile method that can be applied in industry to the simultaneous assessment the level of microbiological contamination and for detection of mites in cereals grains and coffee beans.

Coriander (Coriandrum sativum L.): a potential source of high-value components for functional foods and nutraceuticals--a review

Coriander (Coriandrum sativum L.), a herbal plant, belonging to the family Apiceae, is valued for its culinary and medicinal uses. All parts of this herb are in use as flavoring agent and/or as traditional remedies for the treatment of different disorders in the folk medicine systems of different civilizations. The plant is a potential source of lipids (rich in petroselinic acid) and an essential oil (high in linalool) isolated from the seeds and the aerial parts. Due to the presence of a multitude of bioactives, a wide array of pharmacological activities have been ascribed to different parts of this herb, which include anti-microbial, anti-oxidant, anti-diabetic, anxiolytic, anti-epileptic, anti-depressant, anti-mutagenic, anti-inflammatory, anti-dyslipidemic, anti-hypertensive, neuro-protective and diuretic. Interestingly, coriander also possessed lead-detoxifying potential. This review focuses on the medicinal uses, detailed phytochemistry, and the biological activities of this valuable herb to explore its potential uses as a functional food for the nutraceutical industry.

Eryngium foetidum L.: a review

Eryngium foetidum L. is a biennial herb which is used extensively as a medicinal plant in most tropical regions. It is of increasing importance as a spice plant cultivated in India, Vietnam, Australia and elsewhere with well documented procedures for maximum yield. It also possesses a wide range of ethnomedicinal uses including treatment for burns, earache, fevers, hypertension, constipation, fits, asthma, stomach ache, worms, infertility complications, snake bites, diarrhea and malaria. Chemical evaluation of the leaves indicated the presence of flavonoids, tannins, a saponin and several triterpenoids; but no alkaloids were reported. A significant constituent of the essential oil of the plant is E-2-dodecenal ("eryngial"), with isomers of trimethylbenzaldehyde being present in lesser proportions. Variability in the composition of essential oil was clearly dependent on the geographic location of the growing plant. Pharmacological studies of the aerial plant parts have demonstrated anthelmintic activity due to eryngial, anti-inflammatory action due to the phytosterol fractions, anti-convulsant activity in the respective models, and selective antibacterial activity against Salmonella species and the Erwinia genus of bacteria. A fraction of the essential oil rich in eryngial is the subject of a US patent application for its effectiveness against parasitic trypanosomes, nematodes, fungi and bacteria in humans and other mammals. These findings suggest the need for further research of this herb and its products.